摘要
对一台1 000 MW超超临界前后墙旋流对冲燃烧煤粉锅炉,在HT-NR3型低NO_x旋流煤粉燃烧器不同外二次风叶片开度下(50%、75%、100%),进行了炉内流动、燃烧、传热与NO_x排放特性数值模拟研究。模拟结果与试验测量值符合性较好,结果表明:外二次风旋流叶片开度对炉内燃烧特性及排放特性影响较大,旋流叶片开度减小导致旋流强度增大,卷吸高温烟气增多,煤粉着火距离减小,煤粉燃烧剧烈程度增加,炉内主燃区温度水平升高,燃尽区温度水平有所降低,煤粉燃烬率增大,NO_x排放量减小。实际运行中采用外二次风开度为50%的高旋流强度工况,达到了燃烧稳定、高效低NO_x的目的。
The effects of different outer secondary-air vane opening degrees(50%、75%、100%)on the flow,combustion,heat transfer and NOx emission are simulated for a1000MW ultra-supercritical pulverized-coal opposed swirling utility boiler.The numerical results agree with the measured value well.The results show that the out-secondary air swirling blade opening degree has a significant influence on the combustion and NOx emissions.With decreasing the opening degree,the swirl intensity increases,the ignition distance decreases,the average temperature increases in the main burning region and decreases in the burnout region,the burnout rate also increases,and NOx emissions decreases.The actual operation adoptes the swirling opening degree of50%,the stable flame,high-effeciency combustion and low NOx are achieved.
作者
李超亮
LI Chaoliang(Guodian Hanchuan Power Generation Co., Ltd., Xiaogan Hubei 432300, China)
出处
《湖北电力》
2017年第5期25-31,共7页
Hubei Electric Power
关键词
超超临界
旋流对冲
外二次风
数值模拟
ultra-supercritical
opposed swirling
outer secondary-air
numerical simulation
